Need help on window() function of the 'zoo' package

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Hello,

Actually, Dat_zoo is not a matrix, it is an object of classes "zooreg" 
and "zoo", with a dim attribute:

class(Dat_zoo)
dim(Dat_zoo)

And the output of window() is of the same classes but without a dim 
attribute:

wnd <- window(Dat_zoo, start = as.Date("2001-01-02"))
class(wnd)
dim(wnd)  # NULL

You can set the dim attribute manually like this:

dim(wnd) <- c(length(wnd), 1)

Hope this helps,

Rui Barradas

Em 08-06-2013 22:02, Ron Michael escreveu:
Hi,

I observed that if I use window() function available with the 'zoo' package to extract a portion of my times series and if that time series data is stored in some 'zoo' object with only 1 column, then the resulting zoo object is becoming vector.

Here is my observation:

library(zoo)
Dat <- matrix(1:3, nc = 1)
Dat
      [,1]
[1,]    1
[2,]    2
[3,]    3
Dat_zoo <- zooreg(Dat, start = as.Date("2001-01-01"), frequency = 1)
Dat_zoo
2001-01-01 1
2001-01-02 2
2001-01-03 3
window(Dat_zoo, start = as.Date("2001-01-02"))   ### why it is becoming vector? I want to retain it as matrix only
2001-01-02 2001-01-03
          2          3

Here you can see that, originally my 'Dat_zoo ' object was basically a matrix. However once I use window() function, it became vector.

Is there any possibility to retain the shape of the original object, particularly if that object is matrix with 1 column?

Thank you very much for your help.
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